Romney Hasn’t Done His Homework

MITT ROMNEY’S latest controversial remark, about the role of culture in explaining why some countries are rich and powerful while others are poor and weak, has attracted much comment. I was especially interested in his remark because he misrepresented my views and, in contrasting them with another scholar’s arguments, oversimplified the issue.

It is not true that my book “Guns, Germs and Steel,” as Mr. Romney described it in a speech in Jerusalem, “basically says the physical characteristics of the land account for the differences in the success of the people that live there. There is iron ore on the land and so forth.”

That is so different from what my book actually says that I have to doubt whether Mr. Romney read it. My focus was mostly on biological features, like plant and animal species, and among physical characteristics, the ones I mentioned were continents’ sizes and shapes and relative isolation. I said nothing about iron ore, which is so widespread that its distribution has had little effect on the different successes of different peoples. (As I learned this week, Mr. Romney also mischaracterized my book in his memoir, “No Apology: Believe in America.”)

That’s not the worst part. Even scholars who emphasize social rather than geographic explanations — like the Harvard economist David S. Landes, whose book “The Wealth and Poverty of Nations” was mentioned favorably by Mr. Romney — would find Mr. Romney’s statement that “culture makes all the difference” dangerously out of date. In fact, Mr. Landes analyzed multiple factors (including climate) in explaining why the industrial revolution first occurred in Europe and not elsewhere.

Just as a happy marriage depends on many different factors, so do national wealth and power. That is not to deny culture’s significance. Some countries have political institutions and cultural practices — honest government, rule of law, opportunities to accumulate money — that reward hard work. Others don’t. Familiar examples are the contrasts between neighboring countries sharing similar environments but with very different institutions. (Think of South Korea versus North Korea, or Haiti versus the Dominican Republic.) Rich, powerful countries tend to have good institutions that reward hard work. But institutions and culture aren’t the whole answer, because some countries notorious for bad institutions (like Italy and Argentina) are rich, while some virtuous countries (like Tanzania and Bhutan) are poor.

A different set of factors involves geography, which embraces many more aspects than the physical characteristics Mr. Romney dismissed. One such geographic factor is latitude, which has big effects on wealth and power today: tropical countries tend to be poorer than temperate-zone countries. Reasons include the debilitating effects of tropical diseases on life span and work, and the average lower productivity of agriculture and soils in the tropics than in the temperate zones.

A second factor is access to the sea. Countries without a seacoast or big navigable rivers tend to be poor, because transport costs overland or by air are much higher than transport costs by sea.

A third geographic factor is the history of agriculture. If an extraterrestrial had toured earth in the year 2000 B.C., the visitor would have noticed that centralized government, writing and metal tools were already widespread in Eurasia but hadn’t yet appeared in the New World, sub-Saharan Africa or Australia. That long head start would have let the visitor predict correctly that today, most of the world’s richest and most powerful countries would be Eurasian countries (and their overseas settlements in North America, Australia and New Zealand).

The reason is the historical effect of geography: 13,000 years ago, all peoples everywhere were hunter-gatherers living in sparse populations without centralized government, armies, writing or metal tools. These four roots of power arose as consequences of the development of agriculture, which generated human population explosions and accumulations of food surpluses capable of feeding full-time leaders, soldiers, scribes and inventors. But agriculture could originate only in those few regions endowed with many wild plant and animal species suitable for domestication, like wild wheat, rice, pigs and cattle.

In short, geographic explanations and cultural-institutional explanations aren’t independent of each other. Of course, not all agricultural regions developed honest centralized government, but no nonagricultural region ever developed any centralized government, whether honest or dishonest. That’s why institutions promoting wealth today arose first in Eurasia, the area with the oldest and most productive agriculture.

What does this mean for Americans? Can we assume that the United States, blessed with temperate location and seacoasts and navigable rivers, will remain rich forever, while tropical or landlocked countries are doomed to eternal poverty?

Of course not. Some tropical and subtropical countries have become richer despite geographic limitations. They’ve invested in public health to overcome their disease burdens (Botswana and the Philippines). They’ve invested in crops adapted to the tropics (Brazil and Malaysia). They’ve focused their economies on sectors other than agriculture (Singapore and Taiwan).

Conversely, geographic advantages don’t guarantee permanent success, as the growing difficulties in Europe and America show. We Americans fail to provide superior education and economic incentives to much of our population. India, China and other countries that have not been world leaders are investing heavily in education, technology and infrastructure. They’re offering economic opportunities to more and more of their citizens. That’s part of the reason jobs are moving overseas. Our geography won’t keep us rich and powerful if we can’t get a good education, can’t afford health care and can’t count on our hard work’s being rewarded by good jobs and rising incomes.

Mitt Romney may become our next president. Will he continue to espouse one-factor explanations for multicausal problems, and fail to understand history and the modern world? If so, he will preside over a declining nation squandering its advantages of location and history.

Jared Diamond, a professor of geography at the University of California, Los Angeles, is the author of the forthcoming book “The World Until Yesterday: What Can We Learn From Traditional Societies?”

A version of this op-ed appears in print on August 2, 2012, on page A21 of the New York edition with the headline: Romney Hasn’t Done His Homework. Today's Paper|Subscribe